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A381203 a(n) is the lcm of the elements of the set of bases and exponents in the prime factorization of n.

%I A381203 #10 Feb 18 2025 18:57:34
%S A381203 2,3,2,5,6,7,6,6,10,11,6,13,14,15,4,17,6,19,10,21,22,23,6,10,26,3,14,
%T A381203 29,30,31,10,33,34,35,6,37,38,39,30,41,42,43,22,30,46,47,12,14,10,51,
%U A381203 26,53,6,55,42,57,58,59,30,61,62,42,6,65,66,67,34,69,70,71
%N A381203 a(n) is the lcm of the elements of the set of bases and exponents in the prime factorization of n.
%C A381203 Differs from A381201 at n = 16, 48, 64, 80, 112, 144, 162, 176, 192, ... = A381213.
%H A381203 Paolo Xausa, <a href="/A381203/b381203.txt">Table of n, a(n) for n = 2..10000</a>
%e A381203 a(12) = 6 because 12 = 2^2*3^1, the set of these bases and exponents is {1, 2, 3} and lcm(1, 2, 3) = 6.
%e A381203 a(31500) = 210 because 31500 = 2^2*3^2*5^3*7^1, the set of these bases and exponents is {1, 2, 3, 5, 7} and lcm(1, 2, 3, 5, 7) = 210.
%t A381203 A381203[n_] := LCM @@ Flatten[FactorInteger[n]];
%t A381203 Array[A381203, 100, 2]
%o A381203 (PARI) a(n) = my(f=factor(n)); lcm(setunion(Set(f[,1]), Set(f[,2]))); \\ _Michel Marcus_, Feb 18 2025
%Y A381203 Cf. A381201, A381202, A381204, A381205, A381213.
%K A381203 nonn,easy
%O A381203 2,1
%A A381203 _Paolo Xausa_, Feb 17 2025